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treatment with triterpenic fraction purified from baccharis uncinella leaves inhibits leishmania (leishmania) amazonensis spreading and improves th1 immune response in infected mice.the current medications used to treat leishmaniasis have many side effects for patients; in addition, some cases of the disease are refractory to treatment. therefore, the search for new leishmanicidal compounds is indispensable. recently, it was demonstrated that oleanolic- and ursolic-containing fraction from baccharis uncinella leaves eliminated the promastigote and amastigote forms of leishmania (leishmania) amazonensis and l. (viannia) braziliensis without causing toxic effects for j774 mac ...201424173812
a2 and other visceralizing proteins of leishmania: role in pathogenesis and application for vaccine development.visceral leishmaniasis is a re-emergent disease and a significant cause of morbidity worldwide. amongst the more than 20 leishmania species, leishmania donovani, leishmania infantum and more rarely leishmania amazonensis are associated with visceral leishmaniasis. a major question in leishmaniasis research is how these species migrate to and infect visceral organs whereas other species such as leishmania major and leishmania braziliensis remain in the skin, causing tegumentary leishmaniasis. her ...201424264241
brazilian brown propolis elicits antileishmanial effect against promastigote and amastigote forms of leishmania amazonensis.propolis is a complex matrix of chemical constituents extracted from plants and produced by bees which is used in folk medicine due to its several pharmacological properties. its chemical composition varies according to the region where it is produced. this work has studied the antileishmanial activity and cytotoxicity of brown propolis (bp) originating from the semi-arid region of piauí, brazil. the bp showed significant inhibition of the leishmania amazonensis promastigotes growth as well as b ...201424261482
synthesis and evaluation of the antiparasitic activity of bis-(arylmethylidene) cycloalkanones.a series of bis-(arylmethylidene)-cycloalkanones was synthesized by cross-aldol condensation. the activity of the compounds was evaluated against amastigotes forms of trypanosoma cruzi and promastigotes forms of leishmania amazonensis. the cytotoxicity of the active compounds on uninfected fibroblasts or macrophages was established in vitro to evaluate the selectivity of their antiparasitic effects. six compounds displayed trypanocidal activity against amastigotes intracellular forms of t. cruzi ...201424321832
leishmania amazonensis: characterization of an ecto-pyrophosphatase activity.several ecto-enzymatic activities have been described in the plasma membrane of the protozoan leishmania amazonensis, which is the major etiological agent of diffuse cutaneous leishmaniasis in south america. these enzymes, including ecto-phosphatases, contribute to the survival of the parasite by participating in phosphate metabolism. this work identifies and characterizes the extracellular hydrolysis of inorganic pyrophosphate related to an ecto-pyrophosphatase activity of the promastigote form ...201424316462
unsymmetrical 1,5-diaryl-3-oxo-1,4-pentadienyls and their evaluation as antiparasitic agents.in this work the synthesis and antiparasitical activity of new 1,5-diaryl-3-oxo-1,4-pentadienyl derivatives are described. first, compounds 1a, 1b, 1c and 1d were prepared by acid-catalyzed aldol reaction between 2-butanone and benzaldehyde, anisaldehyde, p-n,n-dimethylaminobenzaldehyde and p-nitrobenzaldehyde. reacting each of the methyl ketones 1a, 1b, 1c and 1d with the p-substituted benzaldehydes under basic-catalyzed aldol reaction, we further prepared compounds 2a-2p. all twenty compounds ...201424398381
cross-protective effect of a combined l5 plus l3 leishmania major ribosomal protein based vaccine combined with a th1 adjuvant in murine cutaneous and visceral leishmaniasis.two leishmania major ribosomal proteins l3 (lml3) and l5 (lml5) have been described as protective molecules against cutaneous leishmaniasis due to infection with l. major and leishmania braziliensis in balb/c mice when immunized with a th1 adjuvant (non-methylated cpg-oligodeoxynucleotides; cpg-odn). in the present study we analyzed the cross-protective efficacy of an lml3-lml5-cpg odn combined vaccine against infection with leishmania amazonensis and leishmania chagasi (syn. leishmania infantum ...201424382098
understanding the mechanisms controlling leishmania amazonensis infection in vitro: the role of ltb4 derived from human neutrophils.neutrophils are rapidly recruited to the site of leishmania infection and play an active role in capturing and killing parasites. they are the main source of leukotriene b4 (ltb4), a potent proinflammatory lipid mediator. however, the role of ltb4 in neutrophil infection by leishmania amazonensis is not clear. in this study, we show that l. amazonensis or its lipophosphoglycan can induce neutrophil activation, degranulation, and ltb4 production. using pharmacological inhibitors of leukotriene sy ...201424634497
novel targeting using nanoparticles: an approach to the development of an effective anti-leishmanial drug-delivery system.the study reported here aimed to develop an optimized nanoparticle delivery system for amphotericin b (ampb) using a polyelectrolyte complexation technique. for this, two oppositely charged polymers presenting anti-leishmanial activity - chitosan (cs) and chondroitin sulfate (chs) - were used: cs as a positively charged polymer and chs as a negatively charged polymer. the chitosan (nq) nanoparticles, chitosan-chondroitin sulfate (nqc) nanoparticles, and chitosan-chondroitin sulfate-amphotericin ...201424627630
identification and characterization of new leishmania promastigote surface antigens, lapsa-38s and lipsa-50s, as major immunodominant excreted/secreted components of l. amazonensis and l. infantum.we have previously demonstrated that sera from dogs vaccinated with excreted/secreted antigens (esa) of leishmania infantum promastigotes (liesap) mainly recognized an immunodominant antigen of 54 kda. an anti-liesap-specific igg2 humoral response was observed and associated to th1-type response in vaccinated dogs. this response was highly correlated with a long-lasting and strong liesap-vaccine protection toward l. infantum experimental infection. in addition, it was also shown that dogs from t ...201424614507
miltefosine increases lipid and protein dynamics in leishmania amazonensis membranes at concentrations similar to those needed for cytotoxicity activity.miltefosine (mt) is a membrane-active alkylphospholipid licensed for the topical treatment of breast cancer skin metastases and the oral treatment of leishmaniasis, although its mechanism of action remains unclear. electron paramagnetic resonance (epr) spectroscopy of a spin-labeled lipid and a thiol-specific spin label in the plasma membrane of leishmania promastigotes showed that mt causes dramatic increases in membrane dynamics. although these alterations can be detected using a spin-labeled ...201424614380
combination therapy with tamoxifen and amphotericin b in experimental cutaneous leishmaniasis.leishmaniasis chemotherapy remains very challenging. the high cost of active drugs, along with the severity of their side effects and the increasing failure rate of the current therapeutic schemes, calls for the discovery of new active drugs and schemes of treatment. the use of combination therapy has gained much attention in recent years as a possible strategy for overcoming the various shortcomings in the present arsenal. we recently described the effectiveness of tamoxifen in murine models of ...201424550333
potential therapeutic use of herbal extracts in trypanosomiasis.the aim of the present study was to evaluate the effects of crude extracts from handroanthus impetiginosa, ageratum conyzoides, and ruta graveolens on leishmania amazonensis and trypanosoma cruzi infection in vitro. the results showed that the extracts caused significant toxicity in promastigotes and trypomastigotes. a significant decrease in the rate of cell invasion by pretreated trypomastigotes and promastigotes was also observed. the extracts caused a significant reduction of the multiplicat ...201424548158
isolation of arginase inhibitors from the bioactivity-guided fractionation of byrsonima coccolobifolia leaves and stems.byrsonima coccolobifolia leaf and stem extracts were studied in the search for possible leishmanicidal compounds using arginase (arg) from leishmania amazonensis as a molecular target. flavonoids 1b, 1e-1g, 2a, 2b, and 2d-2f showed significant inhibitory activity, with ic50 values ranging from 0.9 to 4.8 μm. the kinetics of the most active compounds were determined. flavonoids 1e, 1f, 2a, 2b, and 2e were characterized as noncompetitive inhibitors of arg with dissociation constants (ki) ranging f ...201424521209
sod1 plasma level as a biomarker for therapeutic failure in cutaneous leishmaniasis.we show that increased plasma superoxide dismutase 1 (sod1) levels are statistically significant predictors of the failure of pentavalent antimony treatment for cutaneous leishmaniasis caused by leishmania braziliensis. in leishmania amazonensis-infected patients, host sod1 levels can be used to discriminate between localized and drug-resistant diffuse cutaneous leishmaniasis. using in situ transcriptomics (ncounter), we demonstrate a significant positive correlation between host sod1 and interf ...201424511100
the calpain inhibitor mdl28170 induces the expression of apoptotic markers in leishmania amazonensis promastigotes.human cutaneous leishmaniasis is caused by distinct species, including leishmania amazonensis. treatment of cutaneous leishmaniasis is far from satisfactory due to increases in drug resistance and relapses, and toxicity of compounds to the host. as a consequence for this situation, the development of new leishmanicidal drugs and the search of new targets in the parasite biology are important goals.201424498160
leishmania braziliensis and leishmania amazonensis amastigote extracts differ in their enhancement effect on leishmania infection when injected intradermally.it has been reported that repeated intravenous injections of a relatively large amount of leishmania amazonensis amastigote extract (lae) in balb/c mice exacerbates the infection of these mice by leishmania braziliensis. the identification of the extract active principle(s) through physicochemical purification often involves dilution and losses of protein in the course of successive purification procedures. the large amount of the extract required to induce the phenomenon, therefore, hinders the ...201424484604
targeted extracellular signal-regulated kinase activation mediated by leishmania amazonensis requires mp1 scaffold.leishmania amazonensis infection promotes alteration of host cellular signaling and intracellular parasite survival, but specific mechanisms are poorly understood. we previously demonstrated that l. amazonensis infection of dendritic cells (dc) activated extracellular signal-regulated kinase (erk), an map-kinase kinase kinase, leading to altered dc maturation and non-healing cutaneous leishmaniasis. studies using growth factors and cell lines have shown that targeted, robust, intracellular phosp ...201424463270
excreted leishmania peruviana and leishmania amazonensis iron-superoxide dismutase purification: specific antibody detection in colombian patients with cutaneous leishmaniasis.leishmania sp. survival in the vertebrate host depends on the host macrophage immune response as well as on the parasite's defense against free radicals. iron-superoxide dismutase (fe-sod) is a key antioxidant enzyme that contributes to radical superoxide dismutation, preventing the disease from surging and propagating itself. leishmania sp. has various fe-sod isoforms, one of which (fe-sode) is excreted into the medium and, being highly immunogenic, can be considered a very good molecular marke ...201424440468
dynamic identification of h2 epitopes from leishmania (leishmania) amazonensis cysteine proteinase b with potential immune activity during murine infection.peptides from the cooh-terminal extension of cysteine proteinase b from leishmania (leishmania) amazonensis (cyspep) can modulate immune responses in vertebrate hosts. with this hypothesis as base, we used the online analysis tool syfpeithi to predict seven epitopes from this region with potential to bind h2 proteins. we performed proliferation tests and quantified reactive t lymphocytes applying a cytometry analysis, using samples from draining lymph node of lesions from l. (l.) amazonensis-inf ...201424436127
complexes of different nitrogen donor heterocyclic ligands with sbcl3 and phsbcl2 as potential antileishmanial agents against sb(iii)-sensitive and -resistant parasites.novel trivalent antimony complexes with the nitrogen donor heterocyclic ligand 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen) or dipyrido[3,2-d:2',3'-f]quinoxaline (dpq) have been synthesized by the reaction with sbcl3 or phsbcl2. the crystal structures of [sb(phen)cl3] and [phsb(phen)cl2]ch3cooh were determined and shown to adopt a distorted square pyramid geometry with a five-coordinated sb center. surprisingly, all the complexes, the ligands and phsbcl2 showed very high antileishmanial ac ...201424412095
in vitro activity of the hydroethanolic extract and biflavonoids isolated from selaginella sellowii on leishmania (leishmania) amazonensis.this study is the first phytochemical investigation of selaginella sellowii and demonstrates the antileishmanial activity of the hydroethanolic extract from this plant (sshe), as well as of the biflavonoids amentoflavone and robustaflavone, isolated from this species. the effects of these substances were evaluated on intracellular amastigotes of leishmania (leishmania) amazonensis, an aetiological agent of american cutaneous leishmaniasis. sshe was highly active against intracellular amastigotes ...201425591109
oral effectiveness of pmic4, a novel hydroxyethylpiperazine analogue, in leishmania amazonensis.pentavalent antimonials have saved the lives of thousands of leishmania-infected patients more than seventy years but, unfortunately, they are highly toxic and require parenteral delivery. therefore, the search for safer and orally delivered alternative is a need. this paper describes the antileishmanial properties of pmic4, a novel hydroxyethylpiperazine analogue. pmic4 showed potent activity against intracellular amastigotes of leishmania amazonensis, with ic50 of 1.8 μm and selectivity index ...201425516829
leishmania braziliensis replication protein a subunit 1: molecular modelling, protein expression and analysis of its affinity for both dna and rna.replication factor a (rpa) is a single-strand dna binding protein involved in dna replication, recombination and repair processes. it is composed by the subunits rpa-1, rpa-2 and rpa-3; the major dna-binding activity resides in the subunit 1 of the heterotrimeric rpa complex. in yeast and higher eukaryotes, besides the three basic structural dna-binding domains, the rpa-1 subunit contains an n-terminal region involved in protein-protein interactions with a fourth dna-binding domain. remarkably, ...201425498946
rpa-1 from leishmania amazonensis (larpa-1) structurally differs from other eukaryote rpa-1 and interacts with telomeric dna via its n-terminal ob-fold domain.replication protein a-1 (rpa-1) is a single-stranded dna-binding protein involved in dna metabolism. we previously demonstrated the interaction between larpa-1 and telomeric dna. here, we expressed and purified truncated mutants of larpa-1 and used circular dichroism measurements and molecular dynamics simulations to demonstrate that the tertiary structure of larpa-1 differs from human and yeast rpa-1. larpa-1 interacts with telomeric ssdna via its n-terminal ob-fold domain, whereas rpa from hig ...201425451229
an optimized nanoparticle delivery system based on chitosan and chondroitin sulfate molecules reduces the toxicity of amphotericin b and is effective in treating tegumentary leishmaniasis.amphotericin b (ampb) is active against leishmaniasis, but its use is hampered due to its high toxicity observed in patients. in this study, a nanoparticles-delivery system for ampb (nqc-ampb), containing chitosan and chondroitin sulfate molecules, was evaluated in balb/c mice against leishmania amazonensis. an in vivo biodistribution study, including biochemical and toxicological evaluations, was performed to evaluate the toxicity of ampb. nanoparticles were radiolabeled with technetium-99m and ...201425429219
protective effects of the antileishmanial extract of tephrosia cinerea (l.) pers. (fabaceae) against cyclophosphamide-induced damage.tephrosia cinerea l. (pers.) is a tropical species that exhibits antileishmanial activity in leishmania amazonensis promastigote cultures and is commonly used to treat infections, inflammations, ulcers, nervous conditions, and diarrhea. however, no studies have investigated its effects on genetic material. therefore, we evaluated the genotoxic potential, antigenotoxic potential, and cytotoxic effects of hydroalcoholic extracts of t. cinerea leaves. in an in vitro genotoxicity study, human periph ...201425366795
pterocarpanquinone lqb-118 induces apoptosis in leishmania (viannia) braziliensis and controls lesions in infected hamsters.previous results demonstrate that the hybrid synthetic pterocarpanquinone lqb-118 presents antileishmanial activity against leishmania amazonensis in a mouse model. the aim of the present study was to use a hamster model to investigate whether lqb-118 presents antileishmanial activity against leishmania (viannia) braziliensis, which is the major leishmania species related to american tegumentary leishmaniasis. the in vitro antileishmanial activity of lqb-118 on l. braziliensis was tested on the ...201425340550
the comparative genomics and phylogenomics of leishmania amazonensis parasite.leishmaniasis is an infectious disease caused by leishmania species. leishmania amazonensis is a new world leishmania species belonging to the mexicana complex, which is able to cause all types of leishmaniasis infections. the l. amazonensis reference strain mhom/br/1973/m2269 was sequenced identifying 8,802 codifying sequences (cds), most of them of hypothetical function. comparative analysis using six leishmania species showed a core set of 7,016 orthologs. l. amazonensis and leishmania mexica ...201425336895
evidences for leishmanicidal activity of the naphthoquinone derivative epoxy-α-lapachone.in this work, we analyze the leishmanicidal effects of epoxy-α-lapachone on leishmania (viannia) braziliensis and leishmania (leishmania) amazonensis. promasigotes and amastigotes (inhabiting human macrophages) from both species were assayed to verify the compound's activity over the distinct morphological stages. the incubation with epoxy-α-lapachone led to a significant decrease in the numbers of promastigotes from both species in the cultures, in a dose-and time-dependent fashion. the surviva ...201425307687
insulin-like growth factor-i induces arginase activity in leishmania amazonensis amastigote-infected macrophages through a cytokine-independent mechanism.leishmania (leishmania) amazonensis exhibits peculiarities in its interactions with hosts. because amastigotes are the primary form associated with the progression of infection, we studied the effect of insulin-like growth factor (igf)-i on interactions between l. (l.) amazonensis amastigotes and macrophages. upon stimulation of infected macrophages with igf-i, we observed decreased nitric oxide production but increased arginase expression and activity, which lead to increased parasitism. howeve ...201425294956
cell death and ultrastructural alterations in leishmania amazonensis caused by new compound 4-nitrobenzaldehyde thiosemicarbazone derived from s-limonene.the treatment of leishmaniasis with pentavalent antimonials is problematic because of their toxicity. investigations of potentially active molecules are important to discover less toxic drugs that are viable economic alternatives for the treatment of leishmaniasis. thiosemicarbazones are a group of molecules that are known for their wide versatility and biological activity. in the present study, we examined the antileishmania activity, mechanism of action, and biochemical alterations produced by ...201425253283
leishmanicidal compounds and potent pparγ activators from renealmia thyrsoidea (ruiz & pav.) poepp. & endl.leaves and rhizomes of renealmia thyrsoidea (ruiz & pav.) poepp. & endl. traditionally used in the yanesha pharmacopoeia to treat skin infections such as leishmaniasis ulcers, or to reduce fever were chemically investigated to identify leishmanicidal compounds, as well as pparγ activators.201425251262
synthesis, leishmanicidal activity and theoretical evaluations of a series of substituted bis-2-hydroxy-1,4-naphthoquinones.a series of eight substituted bis-2-hydroxy-1,4-naphthoquinone derivatives was synthesized through lawsone condensation with various aromatic and aliphatic aldehydes under mild acidic conditions. the title compounds were evaluated for antileishmanial activity in vitro against leishmania amazonensis and leishmania braziliensis promastigotes; six compounds showed good activity without significant toxic effects. the compound with the highest activity was used for an in vivo assay with leishmania am ...201425247686
intranasal vaccination with extracellular serine proteases of leishmania amazonensis confers protective immunity to balb/c mice against infection.previously, we demonstrated that unlike subcutaneous or intramuscular vaccination, intranasal vaccination of balb/c mice with whole leishmania amazonensis antigens leads to protection against cutaneous leishmaniasis. here, the role of parasite serine proteases in the protective immunity was investigated.201425239157
extracellular vesicles from leishmania-infected macrophages confer an anti-infection cytokine-production profile to naïve macrophages.extracellular vesicles (evs) are structures with phospholipid bilayer membranes and 100-1000 nm diameters. these vesicles are released from cells upon activation of surface receptors and/or apoptosis. the production of evs by dendritic cells, mast cells, macrophages, and b and t lymphocytes has been extensively reported in the literature. evs may express mhc class ii and other membrane surface molecules and carry antigens. the aim of this study was to investigate the role of evs from leishmania- ...201425232947
effectiveness of miltefosine-pentoxifylline compared to miltefosine in the treatment of cutaneous leishmaniasis in c57bl/6 mice.the treatment of leishmaniasis ischallenging, given the difficulties in drug administration and resistance. therefore, we chose to test the efficacy of miltefosine combined with pentoxifylline.201425229296
n-butyl-[1-(4-methoxy)phenyl-9h-β-carboline]-3-carboxamide prevents cytokinesis in leishmania amazonensis.leishmaniasis, a complex of diseases caused by protozoa of the genus leishmania, is endemic in 98 countries, affecting approximately 12 million people worldwide. current treatments for leishmaniasis have many disadvantages, such as toxicity, high costs, and prolonged treatment, making the development of new treatment alternatives highly relevant. several studies have verified the antileishmanial activity of β-carboline compounds. in the present study, we investigated the in vitro antileishmanial ...201425224005
the in vitro biological activity of the brazilian brown seaweed dictyota mertensii against leishmania amazonensis.seaweeds present a wide variety of interesting bioactive molecules. in the present work we evaluated the biological activity of the dichloromethane/methanol (2:1) extract (dme) from the brown seaweed dictyota mertensii against leishmania amazonensis and its cytotoxic potential on mammalian cells. the extract showed significant inhibitory effect on the growth of promastigote forms (ic50=71.60 μg/ml) and low toxicity against mammalian cells (cc50=233.10 μg/ml). the dme was also efficient in inhibi ...201425207712
furofuran lignans display schistosomicidal and trypanocidal activities.parasitic diseases continue to be a major worldwide health problem, and there is an urgent need for development of therapeutic drugs. this paper describes synthesis of dehydrodiferulic acid dilactone 1 and dehydrodisinapic acid dilactone 2 furofuran lignans by oxidative coupling of ferulic and sinapic acids, respectively. their schistosomicidal, trypanocidal, and leishmanicidal activities were evaluated in vitro against schistosoma mansoni adult worms, trypomastigote and amastigotes forms of try ...201425200100
an in vitro model of antibody-enhanced killing of the intracellular parasite leishmania amazonensis.footpad infection of c3heb/fej mice with leishmania amazonensis leads to chronic lesions accompanied by large parasite loads. co-infecting these animals with l. major leads to induction of an effective th1 immune response that can resolve these lesions. this cross-protection can be recapitulated in vitro by using immune cells from l. major-infected animals to effectively activate l. amazonensis-infected macrophages to kill the parasite. we have shown previously that the b cell population and the ...201425191842
leishmania amazonensis: increase in ecto-atpase activity and parasite burden of vinblastine-resistant protozoa.leishmania amazonensis is a protozoan parasite that induces mucocutaneous and diffuse cutaneous lesions upon infection. an important component in treatment failure is the emergence of drug-resistant parasites. it is necessary to clarify the mechanism of resistance that occurs in these parasites to develop effective drugs for leishmaniasis treatment. promastigote forms of l. amazonensis were selected by gradually increasing concentrations of vinblastine and were maintained under continuous drug p ...201425176449
leishmania amazonensis infection impairs dendritic cell migration from the inflammatory site to the draining lymph node.in vitro studies show that leishmania infection decreases the adhesion of inflammatory phagocytes to connective tissue by a mechanism dependent on the modulation of integrin function. however, we know little about the influence of this reduction in leukocyte adhesion on parasite dissemination from the infection site.201425142021
antileishmanial activity of medicinal plants used in endemic areas in northeastern brazil.this study investigates the leishmanicidal activity of five species of plants used in folk medicine in endemic areas of the state of alagoas, brazil. data were collected in the cities of colonia leopoldina, novo lino, and união dos palmares, alagoas state, from patients with cutaneous leishmaniasis (leishmania amazonensis) who use medicinal plants to treat this disease. plants extracts were tested at a concentration of 1-100 μg/ml in all experiments, except in an assay to evaluate activity again ...201425126099
resveratrol is active against leishmania amazonensis: in vitro effect of its association with amphotericin b.resveratrol is a polyphenol found in black grapes and red wine and has many biological activities. in this study, we evaluated the effect of resveratrol alone and in association with amphotericin b (amb) against leishmania amazonensis. our results demonstrate that resveratrol possesses both antipromastigote and antiamastigote effects, with 50% inhibitory concentrations (ic50s) of 27 and 42 μm, respectively. the association of resveratrol with amb showed synergy for l. amazonensis amastigotes, as ...201425114129
short-term protection conferred by leishvacin® against experimental leishmania amazonensis infection in c57bl/6 mice.to date, there is no vaccine available against human leishmaniasis. although some vaccination protocols can induce immunity in murine models, they fail to induce protection in humans. the reasons for that remain unclear. the aim of the present study was to characterize the changes in the pattern of the immune response during subcutaneous vaccination with leishvacin® in mice. we also investigated whether ifn-γ and nitric oxide synthase are indispensable for the protection elicited by the vaccine. ...201425102355
terpenes increase the lipid dynamics in the leishmania plasma membrane at concentrations similar to their ic50 values.although many terpenes have shown antitumor, antibacterial, antifungal, and antiparasitic activity, the mechanism of action is not well established. electron paramagnetic resonance (epr) spectroscopy of the spin-labeled 5-doxyl stearic acid revealed remarkable fluidity increases in the plasma membrane of terpene-treated leishmania amazonensis promastigotes. for an antiproliferative activity assay using 5×10(6) parasites/ml, the sesquiterpene nerolidol and the monoterpenes (+)-limonene, α-terpine ...201425101672
the new pyrazolyltetrazole derivative msn20 is effective via oral delivery against cutaneous leishmaniasis.an orally delivered, safe and effective treatment for leishmaniasis is an unmet medical need. azoles and the pyrazolylpyrimidine allopurinol present leishmanicidal activity, but their clinical efficacies are variable. here, we describe the activity of the new pyrazolyltetrazole hybrid, 5-[5-amino-1-(4'-methoxyphenyl)1h-pyrazole-4-yl]1h-tetrazole (msn20). msn20 showed a 50% inhibitory concentration (ic50) of 22.3 μm against amastigotes of leishmania amazonensis and reduced significantly the paras ...201425092697
liposomal formulation of turmerone-rich hexane fractions from curcuma longa enhances their antileishmanial activity.promastigote forms of leishmania amazonensis were treated with different concentrations of two fractions of curcuma longa cortex rich in turmerones and their respective liposomal formulations in order to evaluate growth inhibition and the minimal inhibitory concentration (mic). in addition, cellular alterations of treated promastigotes were investigated under transmission and scanning electron microscopies. liporhic and liporhiwc presented lower mic, 5.5 and 12.5 μg/ml, when compared to nonencap ...201425045693
leishmania amazonensis amastigotes highly express a tryparedoxin peroxidase isoform that increases parasite resistance to macrophage antimicrobial defenses and fosters parasite virulence.professional phagocytes generate a myriad of antimicrobial molecules to kill invading microorganisms, of which nitrogen oxides are integral in controlling the obligate intracellular pathogen leishmania. although reactive nitrogen species produced by the inducible nitric oxide synthase (inos) can promote the clearance of intracellular parasites, some leishmania species/stages are relatively resistant to inos-mediated antimicrobial activity. the underlying mechanism for this resistance remains lar ...201425033301
in vitro and in vivo miltefosine susceptibility of a leishmania amazonensis isolate from a patient with diffuse cutaneous leishmaniasis.miltefosine was the first oral compound approved for visceral leishmaniasis chemotherapy, and its efficacy against leishmania donovani has been well documented. leishmania amazonensis is the second most prevalent species causing cutaneous leishmaniasis and the main etiological agent of diffuse cutaneous leishmaniasis in brazil. driven by the necessity of finding alternative therapeutic strategies for a chronic diffuse cutaneous leishmaniasis patient, we evaluated the susceptibility to miltefosin ...201425033218
in vitro and in vivo activity of benzo[c]phenanthridines against leishmania amazonensis.seven benzo[c]phenanthridines, synthetic or isolated from zanthoxylum rhoifolium root bark, were evaluated against leishmania amazonensis axenic amastigotes. five of them were considered leishmanicidal, with ic50 values ranging from 0.03 to 0.54 µm, and were evaluated on intramacrophagic amastigotes of l. amazonensis. chelerythrine displayed the best activity (ic50=0.5 µm), which was in the same range as the reference compound amphotericin b (ic50=0.4 µm). in vivo studies with chelerythrine, avi ...201425029171
in vivo antileishmanial efficacy of miltefosine against leishmania (leishmania) amazonensis.leishmaniasis, a disease caused by parasites of the leishmania genus, constitutes a significant health and social problem in many countries and is increasing worldwide. the conventional treatment, meglumine antimoniate (ma), presents numerous disadvantages, including invasiveness, toxicity, and frequent therapeutic failure, justifying the attempts at finding alternatives to the first-line therapy. we have studied the comparative long-term efficacy of ma against miltefosine (mf) in leishmania inf ...201425014108
functional properties and stability of spray-dried pigments from bordo grape (vitis labrusca) winemaking pomace.the stability of anthocyanin and phenolic compounds, the antioxidant capacity, the antimicrobial activity and the capacity to inhibit arginase from leishmania were evaluated in spray-dried powders from bordo grape winemaking pomace extract. the pigments were produced using maltodextrin as the carrier agent at concentrations varying from 10% to 30% and air entrance temperatures varying from 130 to 170°c. a sample of freeze-dried extract without the carrier was also evaluated. the anthocyanins in ...201424996348
nlr proteins and parasitic disease.parasitic diseases are a serious global health concern. many of the most common and most severe parasitic diseases, including chagas' disease, leishmaniasis, and schistosomiasis, are also classified as neglected tropical diseases and are comparatively less studied than infectious diseases prevalent in high income nations. the nlrs (nucleotide-binding domain leucine-rich-repeat-containing proteins) are cytosolic proteins known to be involved in pathogen detection and host response. the role of nl ...201424989828
leishmania donovani nucleoside hydrolase terminal domains in cross-protective immunotherapy against leishmania amazonensis murine infection.nucleoside hydrolases of the leishmania genus are vital enzymes for the replication of the dna and conserved phylogenetic markers of the parasites. leishmania donovani nucleoside hydrolase (nh36) induced a main cd4(+) t cell driven protective response against l. chagasi infection in mice which is directed against its c-terminal domain. in this study, we used the three recombinant domains of nh36: n-terminal domain (f1, amino acids 1-103), central domain (f2 aminoacids 104-198), and c-terminal do ...201424966857
synthesis and antiparasitic activity of new bis-arylimidamides: db766 analogs modified in the terminal groups.fifteen novel bis-arylimidamide derivatives with various 6-membered (7a-c) and 5-membered (7d-o) heterocyclic rings replacing the terminal pyridyl rings of the lead compound db766{(2,5-bis[2-i-propoxy-4-(2-pyridylimino)aminophenylfuran]}, were prepared and evaluated versus trypanosoma cruzi, leishmania amazonensis, trypanosoma brucei rhodesiense and plasmodium falciparum. compound 7a with pyrimidine replacing the pyridine rings showed good activity versus t. cruzi, t. brucei rhodesiense and p. f ...201424956553
cell death in amastigote forms of leishmania amazonensis induced by parthenolide.leishmania amazonensis infection results in diverse clinical manifestations: cutaneous, mucocutaneous or visceral leishmaniasis. the arsenal of drugs available for treating leishmania infections is limited. therefore, new, effective, and less toxic leishmaniasis treatments are still needed. we verified cell death in amastigote forms of leishmania amazonensis induced by the sesquiterpene lactone parthenolide.201424913205
leishmanicidal activities of novel synthetic furoxan and benzofuroxan derivatives.a novel series of furoxan (1,2,5-oxadiazole 2-oxide) (compounds 3, 4a and -b, 13a and -b, and 14a to -f) and benzofuroxan (benzo[c][1,2,5]oxadiazole 1-oxide) (compounds 7 and 8a to -c) derivatives were synthesized, characterized, and evaluated for in vitro activity against promastigote and intracellular amastigote forms of leishmania amazonensis. the furoxan derivatives exhibited the ability to generate nitric oxide at different levels (7.8% to 27.4%). the benzofuroxan derivative 8a was able to ...201424913171
in vitro and in vivo activity of major constituents from pluchea carolinensis against leishmania amazonensis.the search for new therapeutic agents from natural sources has been a constant for the treatment of diseases such as leishmaniasis. herein, in vitro and in vivo pharmacological activities of pure major phenolic constituents (caffeic acid, chlorogenic acid, ferulic acid, quercetin, and rosmarinic acid) from pluchea carolinensis against leishmania amazonensis are presented. pure compounds showed inhibitory activity against promastigotes (ic50 = 0.2-0.9 μg/ml) and intracellular amastigotes (ic50 =  ...201424906989
antileishmanial activity and cytotoxicity of brazilian plants.leishmaniasis is a major public health problem, and the alarming spread of parasite resistance has increased the importance of discovering new therapeutic products. the present study aimed to investigate the in vitro leishmanicidal activity from 16 different brazilian medicinal plants. stationary-phase promastigotes of leishmania amazonensis and murine macrophages were exposed to 44 plant extracts or fractions for 48 h at 37°c, in order to evaluate their antileishmanial activity and cytotoxicity ...201424846006
cross-protective immunity to leishmania amazonensis is mediated by cd4+ and cd8+ epitopes of leishmania donovani nucleoside hydrolase terminal domains.the nucleoside hydrolase (nh) of leishmania donovani (nh36) is a phylogenetic marker of high homology among leishmania parasites. in mice and dog vaccination, nh36 induces a cd4+ t cell-driven protective response against leishmania chagasi infection directed against its c-terminal domain (f3). the c-terminal and n-terminal domain vaccines also decreased the footpad lesion caused by leishmania amazonensis. we studied the basis of the crossed immune response using recombinant generated peptides co ...201424822054
arrabidaea chica hexanic extract induces mitochondrion damage and peptidase inhibition on leishmania spp.currently available leishmaniasis treatments are limited due to severe side effects. arrabidaea chica is a medicinal plant used in brazil against several diseases. in this study, we investigated the effects of 5 fractions obtained from the crude hexanic extract of a. chica against leishmania amazonensis and l. infantum, as well as on the interaction of these parasites with host cells. promastigotes were treated with several concentrations of the fractions obtained from a. chica for determination ...201424818162
antileishmanial activity of the estrogen receptor modulator raloxifene.the treatment of leishmaniasis relies mostly on parenteral drugs with potentially serious adverse effects. additionally, parasite resistance in the treatment of leishmaniasis has been demonstrated for the majority of drugs available, making the search for more effective and less toxic drugs and treatment regimens a priority for the control of leishmaniasis. the aims of this study were to evaluate the antileishmanial activity of raloxifene in vitro and in vivo and to investigate its mechanism of ...201424810565
in vitro and in vivo antileishmania activity of sesquiterpene lactone-rich dichloromethane fraction obtained from tanacetum parthenium (l.) schultz-bip.the discovery of new treatments for neglected diseases, including leishmaniasis, is a substantial challenge for scientific research. plant extracts have shown potential in the selective treatment of tropical diseases. the present study evaluated the in vitro and in vivo antileishmania effects of a sesquiterpene lactone-rich dichloromethane fraction (df) obtained from the aerial parts of tanacetum parthenium (l.) schultz-bip. in vitro studies of the df indicated an ic50 of 2.40±0.76 μg ml(-1) aga ...201424810433
periodate-oxidized atp modulates macrophage functions during infection with leishmania amazonensis.previously, we showed that treating macrophages with atp impairs the intracellular growth of leishmania amazonensis, and that the p2x7 purinergic receptor is overexpressed during leishmaniasis. in the present study, we directly evaluated the effect of periodate-oxidized atp (oatp) on parasite control in leishmania-infected macrophages. we found that oatp impaired the attachment/entrance of l. amazonensis promastigotes to c57bl/6 mouse macrophages in a p2x7 receptor-independent manner, as macroph ...201424804957
leishmanicidal evaluation of tetrahydroprotoberberine and spirocyclic erythrina-alkaloids.leishmaniasis is one of the world's most problematic diseases in developing countries. traditional medicines to treat leishmaniasis have serious side effects, as well as significant parasite resistance problems. in this work, two alkaloids 1 and 2 were obtained from corydalis govaniana wall and seven alkaloids 3-9, were obtained from erythrina verna. the structures of the compounds were confirmed by mass spectrometry and 1d- and 2d-nmr spectroscopy. the leishmanicidal activity of compounds 1-9 a ...201424802983
antileishmanial activity of essential oil from chenopodium ambrosioides and its main components against experimental cutaneous leishmaniasis in balb/c mice.chenopodium ambrosioides have been used during centuries by native people to treat parasitic diseases.201424768411
leishmania amazonensis promastigotes in 3d collagen i culture: an in vitro physiological environment for the study of extracellular matrix and host cell interactions.leishmania amazonensis is the causative agent of american cutaneous leishmaniasis, an important neglected tropical disease. once leishmania amazonensis is inoculated into the human host, promastigotes are exposed to the extracellular matrix (ecm) of the dermis. however, little is known about the interaction between the ecm and leishmania promastigotes. in this study we established l. amazonensis promastigote culture in a three-dimensional (3d) environment mainly composed of collagen i (col i). t ...201424765565
role of protein kinase r in the killing of leishmania major by macrophages in response to neutrophil elastase and tlr4 via tnfα and ifnβ.in cutaneous leishmaniasis, leishmania amazonensis activates macrophage double-stranded, rna-activated protein kinase r (pkr) to promote parasite growth. in our study, leishmania major grew normally in raw cells, raw-expressing dominant-negative pkr (pkr-dn) cells, and macrophages of pkr-knockout mice, revealing that pkr is dispensable for l. major growth in macrophages. pkr activation in infected macrophages with poly i:c resulted in parasite death. fifty percent of l. major-knockout lines for ...201424732131
leukotriene b4 modulates p2x7 receptor-mediated leishmania amazonensis elimination in murine macrophages.atp is an important signaling molecule in the immune system, and it is able to bind the p2x7 purinergic receptor. recently, our group showed that atp-treated macrophages eliminate leishmania amazonensis. it has been reported that leukotriene b4 (ltb4) reduces the parasitic load of infected macrophages. additionally, it has been demonstrated that the p2x7 receptor can induce pla2 activation and arachidonic acid mobilization. based on these findings, we investigated whether ltb4 is produced upon p ...201424729618
antiparasitic activities of novel ruthenium/lapachol complexes.the present study describes the synthesis, characterization, antileishmanial and antiplasmodial activities of novel diimine/(2,2'-bipyridine (bipy), 1,10-phenanthroline (phen), 4,4'-methylbipyridine (me-bipy) and 4,4'-methoxybipyridine (meo-bipy)/phosphine/ruthenium(ii) complexes containing lapachol (lap, 2-hydroxy-3-(3-33 methyl-2-buthenyl)-1,4-naphthoquinone) as bidentate ligand. the [ru(lap)(pph3)2(bipy)]pf6 (1), [ru(lap)(pph3)2(me-bipy)]pf6 (2), [ru(lap)(pph3)2(meo-bipy)]pf6(3) and[ru(lap)(p ...201424727183
purification and biochemical characterization of three myotoxins from bothrops mattogrossensis snake venom with toxicity against leishmania and tumor cells.bothrops mattogrossensis snake is widely distributed throughout eastern south america and is responsible for snakebites in this region. this paper reports the purification and biochemical characterization of three new phospholipases a2 (pla2s), one of which is presumably an enzymatically active asp49 and two are very likely enzymatically inactive lys49 pla2 homologues. the purification was obtained after two chromatographic steps on ion exchange and reverse phase column. the 2d sds-page analysis ...201424724078
in vitro cytokines profile and ultrastructural changes of microglia and macrophages following interaction with leishmania.in the present study, we assessed morphological changes and cytokine production after in vitro interaction with causative agents of american cutaneous leishmaniasis and compared the microglia and macrophage immune responses. cultures of microglia and macrophages infected with stationary-phase promastigotes of leishmania (viannia) shawi, leishmania (viannia) braziliensis or leishmania (leishmania) amazonensis were evaluated 24, 48 and 72 h after interaction. macrophages only presented the classic ...201424717447
in vitro and in vivo efficacy of novel flavonoid dimers against cutaneous leishmaniasis.treatment of leishmaniasis by chemotherapy remains a challenge because of limited efficacy, toxic side effects, and drug resistance. we previously reported that synthetic flavonoid dimers have potent antipromastigote and antiamastigote activity against leishmania donovani, the causative agent of visceral leishmaniasis. here, we further investigate their leishmanicidal activities against cutaneous leishmania species. one of the flavonoid dimers (compound 39) has marked antipromastigote (50% inhib ...201424687505
correlation between glucose uptake and membrane potential in leishmania parasites isolated from dcl patients with therapeutic failure: a proof of concept.besides infection with drug-resistant parasites, therapeutic failure in leishmaniasis may be caused by altered drug pharmacokinetics, re-infection, and host immunologic compromise. our aim has been to evaluate if relapses that occur in patients suffering from diffuse cutaneous leishmaniasis (dcl) associate with changes in the fitness of infecting organisms. therefore, in isolates from patients suffering dcl, we correlated glucose uptake and plasma membrane potential and compared the results with ...201424671239
activity of anti-cancer protein kinase inhibitors against leishmania spp.there is an urgent need to develop new and effective treatments for poverty-related neglected diseases. in light of the time required to bring a new drug to market and the cost involved (10-15 years, >1 billion us$), one approach to identifying new treatments for diseases like leishmaniasis is to evaluate drugs that are already registered for the treatment of other diseases. this paper describes the anti-leishmanial activities of 10 fda-approved protein kinase inhibitors already available for th ...201424668412
salivary gland homogenates from wild-caught sand flies lutzomyia flaviscutellata and lutzomyia (psychodopygus) complexus showed inhibitory effects on leishmania (leishmania) amazonensis and leishmania (viannia) braziliensis infection in balb/c mice.during the natural transmission of leishmania parasites, the infected sand fly female regurgitates promastigotes into the host's skin together with its saliva. it has been reported that vector saliva contains immunomodulatory molecules that facilitate the establishment of infection. thus, the main objective of this study was to evaluate the specificity of lutzomyia (lu.) flaviscutellata and lu. (psychodopygus) complexus salivas on the infectivity of leishmania (l.) (leishmania) amazonensis and l ...201425476864
discovery of the rapanone and suberonone mixture as a motif for leishmanicidal and antifungal applications.leishmaniasis and fungal infections are significant diseases impacting worldwide public health. treatments have developed greatly over time, however, there is a necessity to discover less toxic drugs, which have greater efficacy and are more economically accessible. this work conducted a screening of cerrado species extracts: connarus suberosus planch. (connaraceae), neea theifera oerst. (nyctaginaceae) and myrcia linearifolia cambess. (myrtaceae) against leishmania (leishmania) amazonensis, der ...201424331757
molecular detection of leishmania in sand flies (diptera: psychodidae: phlebotominae) collected in the caititu indigenous reserve of the municipality of lábrea, state of amazonas, brazil.phlebotominae sand flies are of medical importance because they are vectors of human pathogens, such as protozoa of the genus leishmania ross, etiological agent of american cutaneous leishmaniasis (acl). in lábrea, a municipality in the state of amazonas, brazil, acl is primarily associated with subsistence activities, such as collection and extraction of forest products, undertaken by both indigenous and nonindigenous people. data on acl in indigenous populations are scarce, such that there is ...201426309318
in vitro interaction between paromomycin sulphate and four drugs with leishmanicidal activity against three new world leishmania species.to evaluate in vitro interactions between paromomycin sulphate and the antileishmanial drugs meglumine antimoniate, amphotericin b, miltefosine and azithromycin against intracellular leishmania (leishmania) infantum chagasi, leishmania (viannia) braziliensis and leishmania (leishmania) amazonensis amastigotes in peritoneal mouse macrophages.201423970484
pvd1 defensin, a plant antimicrobial peptide with inhibitory activity against leishmania amazonensis.plant defensins are small cysteine-rich peptides and exhibit antimicrobial activity against a variety of both plant and human pathogens. despite the broad inhibitory activity that plant defensins exhibit against different micro-organisms, little is known about their activity against protozoa. in a previous study, we isolated a plant defensin named pvd1 from phaseolus vulgaris (cv. pérola) seeds, which was seen to be deleterious against different yeast cells and filamentous fungi. it exerted its ...201526285803
characterization of the b cell response to leishmania infection after anti-cd20 b cell depletion.anti-cd20 depletion therapies targeting b cells are commonly used in malignant b cell disease and autoimmune diseases. there are concerns about the ability of b cells to respond to infectious diseases acquired either before or after b cell depletion. there is evidence that the b cell response to existing or acquired viral infections is compromised during treatment, as well as the antibody response to vaccination. our laboratory has an experimental system using co-infection of c3h mice with both ...201526261496
potent in vitro antiproliferative synergism of combinations of ergosterol biosynthesis inhibitors against leishmania amazonensis.leishmaniases comprise a spectrum of diseases caused by protozoan parasites of the leishmania genus. treatments available have limited safety and efficacy, high costs, and difficult administration. thus, there is an urgent need for safer and more-effective therapies. most trypanosomatids have an essential requirement for ergosterol and other 24-alkyl sterols, which are absent in mammalian cells. in previous studies, we showed that leishmania amazonensis is highly susceptible to aryl-quinuclidine ...201526239973
hairless mice as an experimental model of infection with leishmania (leishmania) amazonensis.hrs/j hairless mice have been investigated as an experimental model in cutaneous leishmaniasis induced by leishmania (leishmania) amazonensis. the animals were inoculated with 10(6) promastigotes into the right hind footpad and the course of infection was followed up for 30, 60 and 90 days. balb/c mice were infected and used as control. hairless mice were susceptible to l. (l.) amazonensis infection and a progressive increase in number of parasites and footpad thickness was detected over time. s ...201526234915
the pentavalent antimonial therapy against experimental leishmania amazonensis infection is more effective under the inhibition of the nf-κb pathway.during leishmania infection, host immune response is important to prevent the growth/survival of intracellular amastigotes. in this study, we evaluated in vitro and in vivo whether or not during leishmania amazonensis infection, pentavalent antimonial treatment/therapy could be more effective under tnf-α inhibition. both l. amazonensis-infected macrophages (in vitro model) and mice (in vivo model) were treated with a nuclear factor-κb (nf-κb) inhibitor and with glucantime®, alone and in combined ...201526218282
first detection of leishmania spp. dna in brazilian bats captured strictly in urban areas.leishmania spp. is a protozoan that maintains its life cycle in domestic and wild animals and it may include bats, a population that has increased in urban environments. this study aimed to investigate the presence of leishmania spp. in bats captured strictly in urban areas that are endemic for visceral leishmaniasis. the spleen and skin samples of 488 bats from 21 endemic cities in northwestern são paulo state, brazil, were tested for the presence of leishmania kdna using real-time pcr. differe ...201526209107
in vitro biological action of aqueous extract from roots of physalis angulata against leishmania (leishmania) amazonensis.leishmaniasis is an infectious disease caused by various species of the protozoan parasites of the leishmania genus and transmitted by phlebotomine sandflies. the protozoa multiply in phagocytic cells, mainly macrophages, which play an important role defending the organism from pathogens. the most effective treatment for leishmaniasis is the chemotherapy and besides the high cost, these drugs are toxic and require a long period of treatment. currently, some herbal products are considered an impo ...201526205771
capillary electrophoresis reveals polyamine metabolism modulation in leishmania (leishmania) amazonensis wild type and arginase knockout mutants under arginine starvation.l-arginine is an essential amino acid in leishmania (leishmania) amazonensis metabolism. a key enzyme for parasite l-arginine metabolism is arginase (arg) that uses arginine to produce urea and ornithine, a precursor of polyamine pathway guaranteeing parasite replication in both insect and mammal hosts. there is an alternative pathway to produce ornithine via l-proline and glutamate, but this mechanism is not described in leishmania. in the mammal host, two enzymes can use l-arginine as substrat ...201526202519
novel selective inhibitor of leishmania (leishmania) amazonensis arginase.arginase is a glycosomal enzyme in leishmania that is involved in polyamine and trypanothione biosynthesis. the central role of arginase in leishmania (leishmania) amazonensis was demonstrated by the generation of two mutants: one with an arginase lacking the glycosomal addressing signal and one in which the arginase-coding gene was knocked out. both of these mutants exhibited decreased infectivity. thus, arginase seems to be a potential drug target for leishmania treatment. in an attempt to sea ...201525845502
the efficacy of 2-nitrovinylfuran derivatives against leishmania in vitro and in vivo.despite recent advances in the treatment of some forms of leishmaniasis, the available drugs are still far from ideal due to inefficacy, parasite resistance, toxicity and cost. the wide-spectrum antimicrobial activity of 2-nitrovinylfuran compounds has been described, as has their activity against trichomonas vaginalis and other protozoa. thus, the aim of this study was to test the antileishmanial activities of six 2-nitrovinylfurans in vitro and in a murine model of leishmaniasis. minimum paras ...201525807467
effect of apigenin on leishmania amazonensis is associated with reactive oxygen species production followed by mitochondrial dysfunction.leishmaniasis is an important neglected disease caused by protozoa of the genus leishmania that affects more than 12 million people worldwide. leishmaniasis treatment requires the administration of toxic and poorly tolerated drugs, and parasite resistance greatly reduces the efficacy of conventional medications. apigenin (1), a naturally occurring plant flavone, has a wide range of reported biological effects. in this study, antileishmanial activity of 1 in vitro was investigated, and its mechan ...201525768915
interactions between neutrophils and leishmania braziliensis amastigotes facilitate cell activation and parasite clearance.leishmania braziliensis and leishmania amazonensis are both causative agents of cutaneous leishmaniasis in south america. however, patient prognosis and the host immune response differ considerably depending on the infecting parasite species. the mechanisms underlying these differences appear to be multifactorial, with both host and parasite components contributing to disease outcome. as neutrophils are a prominent component of the inflammatory infiltrate in chronic cutaneous, diffuse cutaneous ...201525766649
therapeutic switching: from antidermatophytic essential oils to new leishmanicidal products.this study examined whether the antidermatophytic activity of essential oils (eos) can be used as an indicator for the discovery of active natural products against leishmania amazonensis. the aerial parts of seven plants were hydrodistilled. using broth microdilution techniques, the obtained eos were tested against three strains of dermatophytes (trichophyton mentagrophytes, microsporum gypseum and microsporum canis). to compare the eos antifungal and antiparasitic effects, the eos activities ag ...201525742270
antileishmanial activity of standardized fractions of stryphnodendron obovatum (barbatimão) extract and constituent compounds.stryphnodendron obovatum benth. is a brazilian tree used to treat skin ulceration, promote wound healing, and inhibit the growth of protozoa, including trypanosoma and leishmania species. bioguided fractionation of the ethanol extract of s. obovatum stem bark was performed, and antileishmanial and antioxidant activities of the standardized fractions were analyzed.201525732835
therapeutic switching: from antidermatophytic essential oils to new leishmanicidal products.this study examined whether the antidermatophytic activity of essential oils (eos) can be used as an indicator for the discovery of active natural products against leishmania amazonensis. the aerial parts of seven plants were hydrodistilled. using broth microdilution techniques, the obtained eos were tested against three strains of dermatophytes (trichophyton mentagrophytes, microsporum gypseum and microsporum canis). to compare the eos antifungal and antiparasitic effects, the eos activities ag ...201525714080
combinations of ascaridole, carvacrol, and caryophyllene oxide against leishmania.to date there are no vaccines against leishmania and chemotherapy remains the mainstay for the control of leishmaniasis. the drugs currently used for leishmaniasis therapy are significantly toxic, expensive, and result in a growing frequency of refractory infections. in this study, we evaluated the effect of combinations of the main components of essential oil from chenopodium ambrosioides (ascaridole, carvacrol, and caryophyllene oxide) against leishmaniaamazonensis. anti-leishmanial effects of ...201525697866
in vitro metacyclogenesis of leishmania (viannia) braziliensis and leishmania (leishmania) amazonensis clinical field isolates, as evaluated by morphology, complement resistance, and infectivity to human macrophages.this study was designed to assess in vitro metacyclogenesis of leishmania (viannia) braziliensis and leishmania (leishmania) amazonensis clinical field isolates obtained from patient lesions (l. braziliensis img3 and pps6m; l. amazonensis mab6). metacyclogenesis was evaluated by different criteria, namely, promastigote size (morphometric analysis and flow cytometry), surface modifications (loss of lectin or monoclonal antibody (mab) binding, complement resistance), and infectivity to human macro ...201525695070
regulation of leishmania (l.) amazonensis protein expression by host t cell dependent responses: differential expression of oligopeptidase b, tryparedoxin peroxidase and hsp70 isoforms in amastigotes isolated from balb/c and balb/c nude mice.leishmaniasis is an important disease that affects 12 million people in 88 countries, with 2 million new cases every year. leishmania amazonensis is an important agent in brazil, leading to clinical forms varying from localized (lcl) to diffuse cutaneous leishmaniasis (dcl). one interesting issue rarely analyzed is how host immune response affects leishmania phenotype and virulence. aiming to study the effect of host immune system on leishmania proteins we compared proteomes of amastigotes isola ...201525692783
4-aminoquinoline derivatives as potential antileishmanial agents.the leishmanicidal activity of a series of 4-aminoquinoline (amq) derivatives was assayed against leishmania amazonensis. this activity against the intracellular parasite was found stronger than for l. amazonensis promastigotes. neither compound was cytotoxic against macrophages. the compound amq-j, which exhibited a strong activity against promastigotes and amastigotes of l. amazonensis (ic50 values of 5.9 and 2.4 μg/ml, respectively) and similar leishmanicidal activity to reference drugs, was ...201525682728
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